The funniest thing about Conker's Bad Fur Day isn't the boozing, sexual situations, drug use, or foul language. It's not even the boss fight against a living mound of feces with teeth made of corn kernels. It's the fact that this Nintendo 64 classic started out a kid's game.

Bad Fur Day isn't the first game in the Conker series. In 1999 developer Rare first released a title called Conker's Pocket Tales for the Game Boy Color, a cutesy single-player adventure in which our hero has to rescue his girlfriend Berri from the Evil Acorn. It's exactly as boring and derivative as it sounds.

And so would have been Twelve Tales: Conker 64, the original title for the Nintendo 64 game introduced at E3 in 1997. Another cute 3D platformer along the same lines as Rare's own Banjo-Kazooie. It had the same look, the same feel, and absolutely no one was looking forward to it.

In an all-too-rare burst of self-awareness, the developers realized the game they had would be a failure, so they changed it.

In 2000 Rare revealed Conker's Bad Fur Day, a nasty, dirty, filthy piece of video game, littered with video games and animal waste. It was so horrible that many retailers decided not to carry it. Warnings were splash all over the box in case parents, mistaking this for a cute and cuddly animal game, scarred their children for life.